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Recently, the natural dyeing process has achieved great importance in the textile wet processing industry due to its clean dyeing, eco-friendliness, and nontoxicity in nature. In the above research project, a unique natural dye extracted from dragon fruit was applied to wool fabric using various mordanting agents to encourage the use of natural dyes and lessen the negative environmental effects caused by synthetic dyeing. The color characteristics (K/S), fastness properties, Fourier transform infrared spectroscopy (FTIR), absorption spectra, and thermal and ultraviolet (UV) resistance of the extracted dye and dyed wool samples were tested and characterized. The K/S values of the dyed wool fabrics were between 5.75 and 13.29. The color fastness ratings obtained from the dyed wool fabric were found to be between good and excellent. Hence, the overall results proved that the novel natural dye obtained from dragon fruit can be utilized for dyeing wool material for the production of eco-friendly and sustainable antimicrobial textiles. [ABSTRACT FROM AUTHOR]

Context: The COVID-19 epidemic has had a substantial influence on the mental health of chronic disease patients. However, there is a scarcity of research on them in Bangladesh. Aims: This study aims to explore the prevalence of and identify the risk factors for depression, anxiety, and stress symptoms during the COVID-19 pandemic among people with chronic diseases in Bangladesh. Materials and Methods: This cross-sectional study involving face-to-face and telephone interviews was carried out among Bangladeshi people diagnosed with chronic diseases between September and November 2020. The total sample size was 878, and a convenient sampling technique was used. Logistic regression analysis was performed to investigate potential influencing factors for depression, anxiety, and stress. Results: The mean age of respondents was 50.10 years. Among them, 35.0%, 36.0%, and 29.0% suffered from depression, anxiety, and stress symptoms, respectively. In multivariable logistic regression, depression had a significant positive association with higher age (≥60 years), lower income, rural residency, and loss of close family members due to COVID-19. Anxiety had a significant positive association with higher age (≥40 years), lower education, lower income, rural residency, and loss of close family members due to COVID-19. Stress had a significant positive association with higher age (≥40 years), no income, rural residency, and loss of close family members due to COVID-19. Conclusion: It is urgent to consider the risk of developing mental health distress among chronic disease patients, especially aged people, by health service providers and generate effective programs for emergency situations. [ABSTRACT FROM AUTHOR]

L-2-Hydroxyglutaric aciduria (L-2-HGA) is a rare disorder. The patients have psychomotor retardation, ataxia, macrocephaly, and epilepsy usually in childhood. We present a case of L-2-HGA who developed dystonia in the third decade of life. The family reported symptoms of progressive psychomotor regression since childhood. On assessment, the patient had mild impairment of higher mental functions, mild exotropia, and right-hand dystonia. Brain MRI revealed diffuse bilateral symmetrical subcortical white matter hyperintense signals. 2-Hydroxyglutaric acid in urine was elevated and the whole genome sequencing revealed a homogeneous pathogenic variant of the L-2-hydroxyglutarate dehydrogenase (L2HGDH) gene. The prognosis was explained to the caregivers. Patients with mild phenotype L-2-HGA can remain undiagnosed until adulthood. Cases of dystonia even without complaints of epilepsy should be investigated by MRI -brain, urine test and genetic testing to rule out L-2-HGA. [ABSTRACT FROM AUTHOR]

Pyrocumulonimbus (pyroCb) thunderclouds, produced from extreme bushfires, can initiate frequent cloud-to-ground (CG) lightning strikes containing extended continuing currents. This, in turn, can ignite new spot fires and inflict massive harm on the environment and infrastructures. This study presents a 3D numerical thundercloud model for estimating the lightning of different types and its striking zone for the conceptual tripole thundercloud structure which is theorized to produce the lightning phenomenon in pyroCb storms. More emphasis is given to the lower positive charge layer, and the impacts of strong wind shear are also explored to thoroughly examine various electrical parameters including the longitudinal electric field, electric potential, and surface charge density. The simulation outcomes on pyroCb thunderclouds with a tripole structure confirm the presence of negative longitudinal electric field initiation at the cloud's lower region. This initiation is accompanied by enhancing the lower positive charge region, resulting in an overall positive electric potential increase. Consequently, negative surface charge density appears underneath the pyroCb thundercloud which has the potential to induce positive (+CG) lightning flashes. With wind shear extension of upper charge layers in pyroCb, the lightning initiation potential becomes negative to reduce the absolute field value and would generate negative (−CG) lightning flashes. A subsequent parametric study is carried out considering a positive correlation between aerosol concentration and charge density to investigate the sensitivity of pyroCb electrification under the influence of high aerosol conditions. The suggested model would establish the basis for identifying the potential area impacted by lightning and could also be expanded to analyze the dangerous conditions that may arise in wind energy farms or power substations in times of severe pyroCb events. [ABSTRACT FROM AUTHOR]

Even though the manufacturing industry consumes roughly 54% of total available energy globally, little consideration has been devoted to optimizing energy in the early stages of industry design, particularly in densely populated cities. With the increased demand for green buildings, energy performance has a greater influence on design results. As a result, this paper provides an envelope optimization technique that can assist architects and computational designers in analyzing the environmental performance of various alternatives and developing optimal design solutions, especially for Bangladesh and the building of these regions. First, an existing industrial site in Dhaka, Bangladesh's capital was chosen as a case study, and a hypothetical industry building, as well as its surroundings, were parametrically developed. Then, for the optimization method, the design factors linked to the building envelopes were chosen. Finally, a Multi-objective Optimization (MOO) procedure was utilized for defining performance measures including daylighting, energy and comfort measures, UDI, EUI, and PPD. According to the MOO results, the UDI may be enhanced by 25.286% as compared to the least favorable scenario. Consequently, the EUI may decreased by 38.718 kWh/m² while the PPD can be increased by 41.78%. The geometric configuration of East, West, North, and South played a significant role when designing the industrial building. According to the analysis, the geometric configuration of a South WWR of 50%, a West WWR of 30%, an East WWR of 70%, and a sill height of 0.75m is the most feasible option. A statistical analysis of design factors and performance measures demonstrated that the window-to-wall ratio, particularly on south walls, has the greatest impact on industrial building design in densely populated areas. The proposed approach is expected to be used by architects and municipal planners to develop design metrics based on simulation results. [ABSTRACT FROM AUTHOR]

This research presents a comprehensive investigation and optimization of the Pt/AlN Schottky Barrier diode (SBD) using technology computer-aided design (TCAD) modeling. The study explores the electrical characteristics of AlN SBDs with various metal contacts, including Aluminum (Al), Silver (Ag), Tungsten (W), Gold (Au), Nickel (Ni), and Platinum (Pt). Through the comparative analyses of different metal/AlN Schottky contacts, the Pt/AlN structure emerges as the most promising due to its superior barrier height and lower leakage current. At 3 0 0 ∘ K, the diode demonstrates a barrier height of 2.72 V, a nearly ideal leakage current of 0.046 pA, and a breakdown voltage of 363 V. The research extends to examining the temperature-dependent electrical behavior of Pt/AlN Schottky diodes, particularly for high-power and high-temperature applications. Analysis carried out across temperatures ranging from 3 0 0 ∘ K to 5 5 0 ∘ K reveals a trend of increasing ON resistance and consistently lower leakage current with rising temperature. Importantly, the study indicates that the impact of temperature on the barrier height and breakdown voltage of the diode is negligible, thus rendering it suitable for high-temperature operation. Leveraging the unique properties of AlN as an ultra-wide bandgap material within the III-V compound semiconductor family, this research provides valuable insights into the potential applications of Pt/AlN Schottky contact. The study highlights that the Pt/AlN Schottky contact is effective not only for high-power, high-temperature SBDs but also as superior metal/semiconductor gate contacts for field-effect transistors (FETs). Their suitability is attributed to their ability to handle high voltages, minimize reverse leakage current, and demonstrate improved thermal stability. [ABSTRACT FROM AUTHOR]